Re: Compression Question
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I haven't a clue about the knock but low compression in one or more cylinders can be burned valves but when in two adjacent cylinders a more likely cause is a blown head gasket. If your engine has mechanical lifters you might first check the tappet clearances and retest the compression.
Posted on: 2011/12/13 22:01
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Re: Compression Question
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Home away from home
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How would one blow a head gasket? I have always driven my car very gently, I hope to goodness this is not something I caused! Is that a huge repair? I think the tappets are hydraulic and they were the suspects in the knocking...
Posted on: 2011/12/13 22:15
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Re: Compression Question
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No, it's not a huge repair - quite the opposite, pretty basic skills and tools only. See
packardclub.org/forum/viewtopic.php?f=14&t=863 How can it happen? Old age, gasket fatigue, improper cylinder head torque, etc.
Posted on: 2011/12/13 22:22
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Re: Compression Question
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Home away from home
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Today is the first day I have seen the car since this happened. Really running rough, kind of chugging... Also noticed the bolts atop the motor (the center ones) have a bit of oil around the nut. This is right above the 2nd and 3rd spark plugs back from the fan. I want to get this done as soon as I can. I have to tell you, this old car has been a stress reliever for me! I need it back soon...
Posted on: 2011/12/14 19:03
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Re: Compression Question
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Also noticed the bolts atop the motor (the center ones) have a bit of oil around the nut. This is right above the 2nd and 3rd spark plugs
Further indication of a failed head gasket.
Posted on: 2011/12/14 22:11
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Re: Compression Question
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Home away from home
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I have to tell you, I am grateful that this could possibly the problem. I also think it has been coming on for a year or so... I have noticed the oil on the bolt(s) for about that time.
Does anyone have a suggestion for a particular place where one would order that gasket? Or a particular type/ style or brand of gasket? Owen, I particularly appreciate your willingness to share your knowledge with me! Thanks abundantly. Paul
Posted on: 2011/12/15 23:27
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Re: Compression Question
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Home away from home
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Try torqueing the head nuts.
Posted on: 2011/12/15 23:32
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VAPOR LOCK demystified: See paragraph SEVEN of PMCC documentaion as listed in post #11 of the following thread:f
packardinfo.com/xoops/html/modules/newbb/viewtopic.php?topic_id=7245 |
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Re: Compression Question
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Paul, you can get a new proper gasket from Kanter Bros., Max Merritt, or Egge, among others. Cost is probably around $125, +/-.
Highly unlikely that retorquing the head bolts will solve the problem at this point, but it takes so little effort that it's worth a try. About 63 lb-ft should be correct; if all are loose, go in a spiral pattern starting in the center and go in a couple of steps. Or you can just use the pattern shown in the shop manual. And don't forget after you install a new gasket, to retorque twice, once after 30 minutes or so of running, and again after a couple of hours. Wouldn't hurt to recheck again after a few months of service. If one or more refuse to tighten to torque, chances are the stud has fatigued and is stretching - replace it (or all of them).
Posted on: 2011/12/16 9:07
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Re: Compression Question
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Just can't stay away
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Owen, Just a dumb question. I have always re-torqued the head once after running the engine for a wile. My, self taught, procedure was to just start with where the bolts were and check the torque from there. Is this the right way or should you loosen them a bit and then re-torque them?
Posted on: 2011/12/18 16:18
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